Management of pregnancy in autoimmune rheumatic diseases: maternal disease course, gestational and neonatal outcomes and use of medications in the prospectiveItalian P-RHEUM.it study

OBJECTIVES

To investigate pregnancy outcomes in women with autoimmune rheumatic diseases (ARD) in the Italian prospective cohort study P-RHEUM.it.

METHODS

Pregnant women with different ARD were enrolled for up to 20 gestational weeks in 29 Rheumatology Centres for 5 years (2018-2023). Maternal and infant information were collected in a web-based database.

RESULTS

We analysed 866 pregnancies in 851 patients (systemic lupus erythematosus was the most represented disease, 19.6%). Maternal disease flares were observed in 135 (15.6%) pregnancies. 53 (6.1%) pregnancies were induced by assisted reproduction techniques, 61 (7%) ended in miscarriage and 11 (1.3%) underwent elective termination. Obstetrical complications occurred in 261 (30.1%) pregnancies, including 2.3% pre-eclampsia. Two cases of congenital heart block were observed out of 157 pregnancies (1.3%) with anti-Ro/SSA. Regarding treatments, 244 (28.2%) pregnancies were treated with glucocorticoids, 388 (44.8%) with hydroxychloroquine, 85 (9.8%) with conventional synthetic disease-modifying anti-rheumatic drugs and 122 (14.1%) with biological disease-modifying anti-rheumatic drugs. Live births were 794 (91.7%), mostly at term (84.9%); four perinatal deaths (0.5%) occurred. Among 790 newborns, 31 (3.9%) were small-for-gestational-age and 169 (21.4%) had perinatal complications. Exclusive maternal breast feeding was received by 404 (46.7%) neonates. The Edinburgh Postnatal Depression Scale was compiled by 414 women (52.4%); 89 (21.5%) scored positive for emotional distress.

CONCLUSIONS

Multiple factors including preconception counselling and treat-to-target with pregnancy-compatible medications may have contributed to mitigate disease-related risk factors, yielding limited disease flares, good pregnancy outcomes and frequency of complications which were similar to the Italian general obstetric population. Disease-specific issues need to be further addressed to plan preventative measures.

Harmonization of ANA testing challenge: quantification strategy to accurately predict end-point titers avoiding serial dilution

Despite the advantages of automated systems for antinuclear antibody (ANA) analysis, the prediction of end-point titers avoiding serial dilutions is still in progress. The aims of this study were to set a conversion table providing discriminant ranges of fluorescence signal intensity values (FI) corresponding to the end-point titers and validate this tool in a real-life laboratory setting. Eight hundred ninety-four serum samples were analyzed for ANA using Image Navigator System. In order to classify FI into non-overlapping groups corresponding to conventional end-point titers, statistical discriminant analysis was used. Validation study was performed calculating agreement and error rates between visual readings and conversion table of 1119 routine ANA positive samples. Setting of FI ranges corresponding to the end-point titers for different staining patterns was computed. For samples showing single pattern, the overall agreement between visual readings and conversion table was 98.4% for all titers ranging from 1:160 to 1:2560, of which 68.0% had the same titer and 30.4% were within ± one titer difference. Concordance rates according to ANA patterns were as follows: (1) nuclear 98.4%, of which 67.0% had the same titer and 31.4% ± one titer; (2) cytoplasmic 100%, of which 72.7% had the same titer and 27.3% than ± one titer; (3) mitotic 66.6%, of which 33.3% had more ± one titer. Our study developed a quantification method for autoantibodies titers assessment based on just one single sample dilution instead of traditional serial dilution approach, providing significant advantages in routine laboratory in terms of reduction in hand-on time and harmonization of results.

An Italian nationwide survey on the evolution of autoantibody diagnostics in autoimmune rheumatic diseases

OBJECTIVES

The advent of new technologies and the discovery of new antigenic targets of autoantibodies has led to significant changes in autoimmune diagnostics worldwide. To address the extent to which autoimmunology laboratories adhere to such innovation in testing and reporting practices, the Italian Society of Clinical Pathology and Laboratory Medicine launched a national survey to assess the current status of autoimmune diagnostics and to provide direction for further harmonisation.

METHODS

A questionnaire covering topics related to the diagnosis of autoimmune systemic rheumatic diseases was distributed to 152 Italian autoimmunology laboratories. The 59 closed-answer questions were subdivided into four main sections: 1. the setting (university, hospital or private laboratory) and the number of tests carried out; 2. the technologies used and their level of automation; 3. the analytical phase (antibody tests and methods), including awareness of the International Consensus on ANA Patterns (ICAP) initiative; 4. reporting of results and clinician relations.

RESULTS

A total of 121 laboratories (79.6%) responded to the survey (15% universities, 70 hospitals, and 15% private laboratories). Indirect immunofluorescence is used by 94.8% of respondents, chemiluminescence by 78.4%, fluoro-immuno-enzymatic assays by 67.5%, immunodot by 52.6%, line-immunoassay by 47.4%, addressable laser bead immunoassay by 10.3% and radioimmunological methods by 10.2%. The great majority of respondents implemented complete automation of the listed methodologies. 65% of participants state that they add an interpretative comment in the report. 45% of participants enjoy a collaborative relationship with clinicians; counselling activities are provided by almost half of participants.

CONCLUSIONS

Survey results indicated that almost all respondent laboratories have broadened their antibody panel and that high-throughput technologies have been widely introduced. Gaps identified by the survey include a still incomplete compliance with guidelines in antibody profiles (e.g. in antiphospholipid syndrome and rheumatoid arthritis and reporting of test results. Awareness of these differences provides insights that may further contribute to achieving harmonisation in autoimmune diagnostics.

Current technologies for anti-ENA antibody detection: State-of-the-art of diagnostic immunoassays

BACKGROUND

Autoantibodies against extractable nuclear antigens (ENA) play a pivotal role in the diagnosis and classification of systemic autoimmune rheumatic diseases (SARD). In recent years, newly developed methods have enabled the simultaneous and quantitative detection of multiple anti-ENA reactivities. However, data regarding the comparability of results obtained using different technologies across different platforms are scarce. In this study we compared eight different immunoassays, commonly used in current laboratory practice for detection of anti-ENA antibodies.

METHODS

Sixty patients suffering from different SARD, 10 inflammatory arthritis patients (disease controls) and 10 healthy blood donors were included in this comparative study. Sera were collected in 15 centers belonging to the Study Group on Autoimmune Diseases of the Italian Society of Clinical Pathology and Laboratory Medicine. We evaluated the analytical sensitivity, specificity and diagnostic accuracy of each method for antibodies to Sm, RNP, Ro60, Ro52, Scl70, CENP-B and Jo1. Cohen's kappa was used to analyze the agreement among methods.

RESULTS

Average agreement among methods was 0.82, ranging from substantial (k = 0.72) to almost perfect (k = 0.92). However, while the specificity was very good for all methods, some differences emerged regarding the analytical sensitivity.

CONCLUSIONS

Diagnostic performance of current technologies for anti-ENA antibody detection showed good comparability. However, as some differences exist among methods, laboratory scientists and clinicians must be aware of the diagnostic accuracy of the testing method in use.

Impact of the COVID-19 Pandemic on the Appropriateness of Diagnostic Pathways of Autoimmune Rheumatic Diseases

OBJECTIVE

Early diagnosis of autoimmune rheumatic diseases (ARDs) is key to achieving effective treatment and improving prognosis. The coronavirus disease 2019 (COVID-19) pandemic has led to major changes in clinical practice on a global scale. We aimed to evaluate the impact of the COVID-19 pandemic on rheumatological clinical practice and autoimmunity testing demands.

METHODS

Data regarding the first rheumatological visits and new diagnoses, together with the autoimmunity laboratory testing volumes related to the COVID-19 pandemic phase (January-December 2020), were collected from medical records and the laboratory information system of a regional reference hospital (Basilicata, Italy) and compared with those obtained during the corresponding period in 2019.

RESULTS

A significant decrease in the 2020 autoimmunity laboratory test volume was found when compared with the same period in 2019 (9912 vs 14,100; P < 0.05). A significant decrease in first rheumatological visits and diagnosis (1272 vs 2336; P < 0.05) was also observed. However, an equivalent or higher percentage of positive autoimmunity results from outpatient services was recorded during 2020 when compared to the prepandemic state. Of note, COVID-19-associated decline in new diagnoses affected mainly less severe diseases. In contrast, ARDs with systemic involvement were diagnosed at the same levels as in the prepandemic period.

CONCLUSION

The COVID-19 pandemic has affected access to health services. However, our study highlighted that during the outbreak, greater appropriateness of the requests for laboratory tests and visits emerged, as shown by a greater percentage of positive test results and new diagnoses of more severe ARDs compared to the prepandemic period.

Serum amyloid A in healthy subjects: assessment of reference value using ELISA method

Serum amyloid A (SAA) is a family of acute-phase reactants. The rise of SAA concentration in blood circulation during the acute-phase response is a clinical marker of active inflammation. Despite its practical and analytical advantages, SAA measurement by enzyme-linked immunosorbent assay (ELISA) has been used mainly as a research tool rather than for the routine laboratory testing. This may be partly explained by the lack of robust reference data in the literature for the different commercially available immunoassays. Using the recommended procedures for the production of reference intervals published by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC), we developed the SAA reference interval for a well-defined Italian healthy population and investigated the correlation among SAA and C-reactive protein (CRP), the commonly used acute-phase marker. After data normalization, the reference cutoff was calculated as 225 ng/ml. A good correlation between SAA and CRP was found (P < .05). No statistically significant differences was found between males and females when the means of SAA values were compared, suggesting that not gender-partitioned reference range is recommended for this analyte. This study allowed to define a widely accepted reference cutoff for the SAA detected by ELISA, responding to an unmet need of laboratory medicine.

A new diagnostic algorithm for pattern-oriented autoantibody testing according to the ICAP nomenclature: A pilot study

The commercial tests currently available as second-level tests to detect ANA sub-specificities are generally used independently from the ANA immunofluorescence (IIF) pattern. The aim of this study was to evaluate the efficacy of the use of a customizable pattern-oriented antigenic panel by immunoblot (IB) using the International Consensus on ANA Patterns (ICAP) classification scheme, in order to introduce a novel and updated autoimmune diagnostic flowchart. 710 sera referred for routine ANA testing were selected on the basis of the ANA pattern according to the ICAP nomenclature (nuclear speckled AC-2,4,5; nucleolar AC-8,9,10,29; cytoplasmic speckled AC-18,19,20) and on an IIF titer ≥1:320. They were then assayed by three experimental IB assays using a panel of selected antigens. ICAP-oriented IB detected 515 antibody reactivities vs. 457 of traditional anti-ENA in the nuclear speckled pattern group, 108 vs. 28 in the nucleolar pattern group, and 43 vs. 34 in the cytoplasmic speckled pattern. This pilot study may lead the way for a new approach introducing an ICAP pattern-oriented follow up testing as a valid alternative to the existing standard panels, thus enabling more patients with autoimmune rheumatic disease to be accurately diagnosed.

FRI0569 SERUM AMYLOID A: ASSESSMENT OF REFERENCE VALUE AND COMPARISON OF SERUM CONCENTRATION IN HEALTHY SUBJECTS AND PATIENTS WITH BEHÇET SYNDROME

Background:

Serum amyloid A (SAA) is a family of acute-phase reactants. The rise of SAA concentration in blood circulation is a clinical marker of active inflammation in several auto-inflammatory diseases, including Behçet syndrome (BS). Despite its practical and analytical advantages, SAA measurement by ELISA has been mainly used as a research tool rather than for the routine laboratory testing due to the lack of a robust reference data in the literature.

Objectives:

Using the recommended procedures of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC), we aimed to develop the SAA reference interval for a well-defined Italian healthy population (HC). Secondly, we compared the SAA serum concentration between HC and patients with BS.

Methods:

Sera specimens were collected from adult healthy blood donors after rule out the exclusion criteria (inflammatory disorders, ongoing infections, pregnancy and breastfeeding, obesity, using oral contraceptives, use of any medication, or consumed of alcohol), and from unselected BS patients fulfilling the International Study Group (ISG) classification criteria. Serum SAA concentrations were detected and quantified with a commercial solid phase sandwich enzyme-linked immunosorbent assay (Human SAA ELISA kit, IBL International GmbH, Hamburg, Germany) used on automated analyzer (Immunomat, SERION Diagnostic, Alifax, Polverara (PD), Italy) according to the manufacturer’s protocol. Statistical analysis and data normalization of HC SAA values were carried out to determine the reference cut off. In the second step of the study, HC and BS patients were stratified in two groups according to the cut-off value.

Results:

We recruited 141 HC (84 M and 57 F; mean age, 44.5±13.2 years) and 63 BS patients (39 M and 24 F mean age, 45.3±13.2 years) assayed for SAA. The reference cut-off was calculated as 225 ng/ml. No statistically significant differences were found between males and females when SAA means were compared, suggesting that not gender-partitioned reference range is recommended for this analyte. After the stratification according to the cut-off value (group 1: < 225 ng/ml and group 2: > 225 ng/ml), we found 53/63 (84.1%) BS patients and 133/141 (94.3%) HC with concentration less than cut-off value, respectively. We identified 10/63 (15.9%) BS patients and 8/141 (5.7%) HC within the second group. The difference was statistically significant (p=0.0177; OR: 3.14, 95% CI: 1.17-3.38).

Conclusion:

This study allowed to define a widely accepted reference cut-off for the SAA detected by ELISA, responding to an unmet need of laboratory medicine. We found a statistically significant higher frequency of BS patients compared with HC when SAA values is higher than cut-off (225 ng/ml). This preliminary data could add significant information for better clarify the role of SAA as biomarker of inflammation and in guidance of clinical practice. Further studies will be required to stratify SAA values in relation to disease activity of BS.

Disclosure of Interests:

Teresa Carbone: None declared, Maria Carmela Padula: None declared, Vito Pafundi: None declared, Carlo Schievano: None declared, Nancy Lascaro: None declared, Angela Padula: None declared, Pietro Leccese: None declared, Salvatore D’Angelo Consultant of: AbbVie, Biogen, BMS, Celgene, Eli Lilly, MSD, Novartis, and UCB, Speakers bureau: AbbVie, BMS, Celgene, Eli Lilly, Novartis, Pfizer, and Sanofi

AB0018 TNFΑ RS1800629 POLYMORPHISM: WHAT ABOUT ITS ASSOCIATION WITH CLINICAL MANIFESTATIONS AND ANTI-TNFΑ THERAPY? DATA FROM A SERIES OF ITALIAN PATIENTS WITH BEHÇET SYNDROME

Background:

Tumor Necrosis Factor-alpha (TNF-α) is a pleiotropic cytokine with a critical role in the pathogenesis of Behçet syndrome (BS). Anti-TNF-α therapy is useful for patients with refractory, severe BS, in particular for ocular, central nervous system, and gastrointestinal manifestations. However, although biological treatment with anti-TNF-α agents are effective in BS, not all patients are definite responders. Non-responders patterns could be due to: alternative non-TNFα related pathway of inflammation; anti-drug antibodies presence or development; polymorphic alleles ofTNFαgene.TNFαrs1800629 (-308G>A) is a drug-response single nucleotide polymorphism (SNP) located within the gene promoter. Poor and conflicting data are currently available about the association of this polymorphism and clinical manifestations of BS, as well as about the responsivness to the TNFα blockers in BS patients [1-3].

Objectives:

Aims of this study were to investigate in a cohort of Italian patients with BS the frequency of rs1800629 genotypes and its association with clinical features and anti-TNFα therapy response.

Methods:

Consecutive patients with BS were recruited. Patients demographic and clinical data were collected by medical records and analyzed. Home-made specific primer pairs were used for rs1800629 coverage. gDNA was isolated and amplified using PCR. Good-quality amplicons were sequenced (Sanger method).In silicoanalysis was downstream performed using specific software for query-subject similarity analysis.

Results:

130 BS patients (64M:66F; mean age: 45.8±12.3 years) were included in the study. Patients predominant lesions were oral aphtosis (100%), eye involvement (86.2%), skin lesions (72.3%) and genital ulcers (57.7%).TNFαrs1800629 wild-type GG genotype was found in 106/130 BS patients (81.5%); the heterozygous genotype (GA) was identified in 24/130 patients (18.5%). No statistically significant differences were found in genotypes frequencies when the patients were stratified for presence and absence of each clinical manifestation (p>0.05), while statistical significant differences were found when the patients were compared for therapy (anti-TNFα drugs) response. In detail, 73/130 patients (56.2%) were treated with anti-TNFα agents. We found 16/73 (21.9%) non-responders patients (NRP). In NRP group, we identified 9/16 patients (56.3%) with GG genotype and 7/16 (43.7%) with GA genotype, while 8/57 (14.0%) responder patients showed GA genotype and 49/57 responder patients (86.0%) showed GG genotype (p=0.0093; OR: 0.21, CI: 0.06-0.729).

Conclusion:

Here we described a low frequency ofTNFαrs1800629 SNP-containing allele and the lack of association between SNP and BS clinical hallmark, as previously reported in literature [1-4]. We also found higher percentage of GG genotype in case of therapy response than GA genotype. The SNP is a promoter polymorphism that could affect the auto-inflammatory response and the therapy responsivness, as suggested by our preliminary data of pharmacogenomics. Analyses of a larger cohort of patients are need to confirm the study findings and to explain the SNP role as outcome predictor.

References:

[1]Touma Z et al. (2010). Arch Med Res 41(2):142-6;

[2]Vallet H et al. (2015). J Autoimmun 62:67-74.

[3]Zhang M et al. (2013). Mol Vis 19:1913-24.

[4]Ateş A et al. (2006). Rheumatol Int 26(4):348-53.

Disclosure of Interests:

Maria Carmela Padula: None declared, Pietro Leccese: None declared, Nancy Lascaro: None declared, Giusi Gaia Sorrento: None declared, Rosa Paola Radice: None declared, Antonina Rita Limongi: None declared, Teresa Carbone: None declared, Angela Padula: None declared, Giuseppe Martelli: None declared, Salvatore D’Angelo Consultant of: AbbVie, Biogen, BMS, Celgene, Eli Lilly, MSD, Novartis, and UCB, Speakers bureau: AbbVie, BMS, Celgene, Eli Lilly, Novartis, Pfizer, and Sanofi

Correlation of Tumor Necrosis Factor-α -308G>A Polymorphism with Susceptibility, Clinical Manifestations, and Severity in Behçet Syndrome: Evidences from an Italian Genetic Case-Control Study

To investigate the association between a functional drug-response tumor necrosis factor (TNF)α gene polymorphism (at the positions of -308; rs1800629; NG_007462.1:g.4682G>A) and both disease susceptibility and clinical manifestations in a cohort of 130 Italian patients with Behçet syndrome (BS). A group of 100 ethnically, age, and gender matched healthy controls (HC) was also recruited. Genotyping was performed using molecular (amplification and direct sequencing) and in silico methods. The genotype distribution of BS patients and HC underlined a lower percentage of wild-type GG genotype in BS patients versus HC (106/130 patients, 81.5% vs. 91/100 HC, 91%; p < 0.05), while the heterozygous genotype (GA) was identified in 24/130 patients (18.5%) versus 9/100 HC (9%) (p < 0.05). GA genotype was significantly associated with the disease (odds ratio = 2.29, 95% confidence interval 1.01-5.18). No significant association was recognized between the single nucleotide polymorphism (SNP) and the BS clinical manifestations, as well as with disease severity (Krause's index). We found statistically significant higher frequency of TNFα rs1800629 GA genotype in patients than in controls. No significant association was recognized between the polymorphism and the clinical parameters, as well as between the SNP and the disease severity. Our data need to be confirmed in larger cohort of patients and matched controls.

Assessing vitamin D levels in an anti-DFS70 positive population: New insights emerging

Background: Anti-dense fine speckled 70 (DFS70) autoantibodies have more often been described in apparently healthy individuals than in patients with systemic autoimmune rheumatic diseases (SARD). The aim of this study was to explore the link between anti-DFS70 autoantibodies and vitamin D (25(OH)D) levels in an Italian adult cohort.Methods: Serum samples from 34 (five males and 29 females) anti-DFS70 positive patients (index cases), 34 ANA-negative healthy controls, 34 ANA-positive anti-DFS70 negative SLE patients, both groups age- and gender-matched with the index cases, 23 ANA-positive anti-DFS70 negative healthy blood donors and six female SARD patients showing mixed DFS positive pattern were collected and tested for 25(OH)D levels. Relevant demographics and lifestyle practices, body mass index (BMI), comorbidities, and use of medication were recorded for patients and healthy controls.Results: Mean serum levels of 25(OH)D were significantly higher in anti-DFS70 positive subjects (mean ± SD: 22.1 ± 9.8 ng/ml) than in ANA-negative healthy controls (mean ± SD: 17.3 ± 6.7 ng/ml; p = .03), ANA-positive healthy controls (mean ± SD: 15.2 ± 6.8 ng/ml; p = .01), SLE patients (16.6 ± 11.0 ng/ml; p = .01) and in patients with SARD (15.0 ± 5.6 ng/ml; p = .01). No statistically relevant differences in BMI, clinical, or demographic parameters were found.Conclusions: Our findings showed higher levels of vitamin D in anti-DFS70 positive subjects than in the controls, which is compatible with the hypothesis of the "benign" nature of anti-DFS70 antibodies.

From structure to function for the characterization of ERAP1 active site in Behçet syndrome. A novel polymorphism associated with known gene variations

INTRODUCTION

ERAP1 has been recently proposed as risk marker of Behçet syndrome (BS). Gene single nucleotide polymorphisms (SNPs) could affect the enzymatic activity and the conserved active site is pivotal for the aminopeptidase function. This study aims to characterize the ERAP1 active site in a cohort of BS patients vs healthy controls (HC) integrating genomics, transcriptomics and bioinformatics approach.

MATERIALS AND METHODS

We recruited 109 consecutive Italian BS patients (63M:46 F; mean age: 45.07 ± 12.28 years) and 106 matched HC (55M:51 F; mean age: 42.57 ± 12.29 years). DNA was isolated and amplified using PCR with home made-primer pairs. PCR products were directly sequenced and computational analyses were performed to search active site SNPs (NCBI-BlastN tool), to predict SNPs functional effect (PolyPhen-2 software) and to obtain protein 3D modelling (Protean3D software). In a second phase of analysis, RNA was extracted and reverse transcribed. Quantitative Real-Time PCR (qPCR) was performed to assess ERAP1 mRNA level in presence (target) and in absence (control) of gene polymorphisms. The Fold change was calculated for the relative quantification of gene expression.

RESULTS

A novel coding variation (NG_027839.1:g.25637 T > G; NP_057526.3:p.Phe360Cys, HGSV nomenclature) was found in heterozygosity state in 5/109 BS patients (4.59 % of cases) and none of HC. It was recognized in association with rs2287987, rs30187, rs17482078, and rs27044 BS-related polymorphisms for 4 out of 5 patients. All patients carrying the novel SNP were HLA-B*51-positive. The novel SNP was released in GenBank database with MK140632.1 ID. The SNP was predicted to be damaging and resides within the Zn-binding HEXXH(X)₁₈E region of the active site, changing the structurally conserved region for the amminopeptidase function. In fact, the change in energy (ΔE) score between wild-type and SNP-containing protein showed a less stable protein in presence of p.Cys360 (ΔE:3.584) (Protean3D prediction). Preliminary qPCR results underlined a significant difference in fold change value when target and control values were compared (p < 0.05), suggesting a reduced expression of ERAP1 mRNA in presence of the novel SNP.

CONCLUSIONS

Our study strengthens the association between ERAP1 and BS. The most significant point was the localization of the novel p.Phe360Cys SNP within the Zn-binding region of protein active site that was predicted to affect its function, causing protein destabilization. Our findings need to be tested in larger genetic studies.

Distribution of rs17482078 and rs27044 ERAP1 polymorphisms in a group of Italian Behçet's syndrome patients: a preliminary case-control study

The Endoplasmic reticulum aminopeptidase protein 1 (ERAP1) trims N-terminal amino acids from epitope precursors for Major Histocompatibility Complex class I presentation. Genome-wide association studies demonstrated that ERAP1 gene single nucleotide polymorphisms (SNPs) are associated with Behçet's syndrome (BS). This study was conducted on the two most consistently BS-associated ERAP1 polymorphisms, rs17482078 (NG_027839.1:g.35983G>A) and rs27044 (NG_027839.1:g.35997C>G) to analyse their distribution in 55 Italian BS patients and 65 ethnically matched controls (healthy controls, HC) and to test their association with BS risk. SNPs were detected by isolation, amplification of genomic DNA and direct sequencing. SNPs functional effects were predicted by bioinformatics software. The odds ratio (OR) with 95% confidence intervals was calculated to assess the strength of BS association for genotypes and alleles, also validated by logistic regression (LR). LR was used to test the association between both SNPs and patients HLA genetic data. Bonferroni correction was also applied. Comparing patients and controls, we found a significant higher frequency of rs17482078 A allele (32.73% BS vs 17.69% HC, p = 0.007) and AA genotype (18.18% BS vs 0% HC; p = 0.0003) and rs27044 G allele (63.64% BS vs 46.92% HC; p = 0.0096) in BS group after Bonferroni correction. No association was found between HLA-B*51 and both ERAP1 SNPs. Although preliminary, our data show a stronger association of rs17482078 with BS compared to rs27044 by means of case-control genetic analysis and bioinformatics prediction of protein structure change. A larger series of patients and controls is required to confirm our preliminary findings.

Identification of a de novo NLRP3 gene variation in an Italian Behçet syndrome patient

A novel nonsynonymous variation of NLRP3 was identified in an Italian patient with Behçet syndrome using both bioinformatics and molecular methods. This variation was a thymine to guanine polymorphism responsible for the isoleucine to serine amino acid change at position 348. The novel variation was predicted to be a pathogenic allele.

A step towards standardization: A method for end-point titer determination by fluorescence index of an automated microscope. End-point titer determination by fluorescence index

OBJECTIVES

Indirect Immunofluorescence (IIF) is widely considered the Gold Standard for Antinuclear Antibody (ANA) screening. However, the high inter-reader variability remains the major disadvantage associated with ANA testing and the main reason for the increasing demand of the computer-aided immunofluorescence microscope. Previous studies proposed the quantification of the fluorescence intensity as an alternative for the classical end-point titer evaluation. However, the different distribution of bright/dark light linked to the nature of the self-antigen and its location in the cells result in different mean fluorescence intensities. The aim of the present study was to correlate Fluorescence Index (F.I.) with end-point titers for each well-defined ANA pattern.

METHODS

Routine serum samples were screened for ANA testing on HEp-2000 cells using Immuno Concepts Image Navigator System, and positive samples were serially diluted to assign the end-point titer. A comparison between F.I. and end-point titers related to 10 different staining patterns was made.

RESULTS

According to our analysis, good technical performance of F.I. (97% sensitivity and 94% specificity) was found. A significant correlation between quantitative reading of F.I. and end-point titer groups was observed using Spearman's test and regression analysis. A conversion scale of F.I. in end-point titers for each recognized ANA-pattern was obtained.

CONCLUSIONS

The Image Navigator offers the opportunity to improve worldwide harmonization of ANA test results. In particular, digital F.I. allows quantifying ANA titers by using just one sample dilution. It could represent a valuable support for the routine laboratory and an effective tool to reduce inter- and intra-laboratory variability.

T-lymphocytes are directly involved in the clinical expression of migratory circinate erythema in epidermolysis bullosa simplex patients

Epidermolysis bullosa simplex with migratory circinate erythema (EBS-MCE) is a rare EBS subtype characterised by migratory blistering lesions that resolve with brownish pigmentation. It is caused by a recurrent readthrough mutation, c.1649delG, in the tail of keratin 5. Here, we report a child with EBS-MCE and investigated the immunologic mechanisms underlying the migratory lesions in this patient. A skin biopsy from the patient from an active border of an erythematous lesion was used for the immunohistochemical characterisation of the inflammatory infiltrate and for TUNEL assay to detect apoptotic cells. We found abundant CD4+ and CD8+ T lymphocytes infiltrating the papillary dermis and lining the dermal-epidermal junction. A number of these cells expressed the activation marker CD69. CD83+ dendritic cells were present both in the epidermis and papillary dermis. Finally, TUNEL staining showed apoptosis of basal and suprabasal keratinocytes. These findings suggest a critical role of the cellular immunity in determining the EBS-MCE phenotype.

CD56highCD16-CD62L- NK cells accumulate in allergic contact dermatitis and contribute to the expression of allergic responses

Allergic contact dermatitis is a common disease caused by an exaggerated T cell-mediated immune response to skin-applied haptens. We show in this study that NK cells affect skin immune responses to haptens by releasing type 1 cytokines and inducing keratinocytes apoptosis. Immunohistochemical stainings demonstrated that NK lymphocytes constitute approximately 10% of the inflammatory infiltrate mostly distributed in the superficial dermis and in the epidermis at the site of intense spongiotic changes. More than 90% of NK cells isolated from allergic contact dermatitis skin showed a CD3-CD56(high)CD16- phenotype by FACS analysis. In addition, they uniformly expressed NKG2A, intermediate to high levels of perforin, and the activating receptors, NKG2D, NKp44, and NKp46, but lacked NKp30 and killer Ig-related receptors. Skin NK lymphocytes displayed a CXCR3+CCR6+CCR5+ chemokine receptor asset for homing into inflamed skin, but not CD62L and CCR7 for lymph node homing. When NK cells from nickel-allergic donors were exposed in vitro to the metal, they failed to proliferate, to upregulate CD69, and to release IFN-gamma, thus indicating that NK lymphocytes do not exhibit memory-like properties to haptens. However, IL-2 released by hapten-driven T lymphocytes rapidly induced the release of IFN-gamma by NK cells and promoted the NK-mediated apoptosis of autologous keratinocytes in a hapten-independent manner. Our findings underline the importance of the interaction between innate and adaptive immune mechanisms for amplification of skin allergic responses to haptens and full expression of allergic contact dermatitis.

Th22 cells represent a distinct human T cell subset involved in epidermal immunity and remodeling

Th subsets are defined according to their production of lineage-indicating cytokines and functions. In this study, we have identified a subset of human Th cells that infiltrates the epidermis in individuals with inflammatory skin disorders and is characterized by the secretion of IL-22 and TNF-alpha, but not IFN-gamma, IL-4, or IL-17. In analogy to the Th17 subset, cells with this cytokine profile have been named the Th22 subset. Th22 clones derived from patients with psoriasis were stable in culture and exhibited a transcriptome profile clearly separate from those of Th1, Th2, and Th17 cells; it included genes encoding proteins involved in tissue remodeling, such as FGFs, and chemokines involved in angiogenesis and fibrosis. Primary human keratinocytes exposed to Th22 supernatants expressed a transcriptome response profile that included genes involved in innate immune pathways and the induction and modulation of adaptive immunity. These proinflammatory Th22 responses were synergistically dependent on IL-22 and TNF-alpha. Furthermore, Th22 supernatants enhanced wound healing in an in vitro injury model, which was exclusively dependent on IL-22. In conclusion, the human Th22 subset may represent a separate T cell subset with a distinct identity with respect to gene expression and function, present within the epidermal layer in inflammatory skin diseases. Future strategies directed against the Th22 subset may be of value in chronic inflammatory skin disorders.

Expression levels of TLRs involved in viral recognition in PBMCs from HIV-1-infected patients failing antiretroviral therapy

OBJECTIVE

The aim of this study was to evaluate whether gene expression of Toll-like receptor (TLR)-3, TLR4, TLR7 and TLR9 was impaired in patients with chronic HIV-1 infection who were failing to respond to antiretroviral therapy.

METHODS

Transcripts encoding TLRs were assayed by quantitative real time RT-PCR on peripheral blood mononuclear cells derived from patients with HIV-1 infection who were responding or not responding to antiretroviral therapy and healthy control subjects.

RESULTS

Chronic HIV-1-infected patients who failed to respond to therapy showed reduced expression of TLRs 3, 4 and 9, together with increased expression of TLR7, as compared to healthy subjects. Moreover, a trend towards a higher expression of TLR3 and TLR9 was observed in responder patients compared with non-responders. In addition, we found lower levels of TRLs 3, 7 and 9 in patients with high levels of HIV-1 RNA compared to those with lower levels of viremia.

CONCLUSIONS

These findings demonstrate that in chronic HIV-1-positive patients who were failing to respond to the therapy, there were substantial changes in TLRs expression. This is likely to be an important determinant of the clinical course of HIV-1 infection.

Parental compliance with home cardiorespiratory monitoring

AIMS

To evaluate parental compliance with home cardiorespiratory monitoring of premature infants with apnoea, siblings of infants who died of sudden infant death syndrome (SIDS), and infants with an apparent life threatening event (ALTE), during the first month of use.

METHODS

A retrospective review of the first month's recordings was conducted on 39 premature infants with apnoea, 13 siblings of SIDS, and 16 infants with ALTE. All infants were singletons. Recommendations during the study period (1992-1994) were for daily use for 23 hours per day. Measurements were average daily hours of use and consistency of use (daily or variable). Gestational age, maternal age, and socioeconomic status as measured by receipt of public assistance were also recorded.

RESULTS

Siblings of SIDS were monitored for fewer hours than were premature or ALTE infants. Only 54% of sibings of SIDS were monitored daily, compared to 87% of premature infants and 93% of ALTEs. Within each diagnostic category socioeconomic status did not affect average hours of monitoring. Consistency of use was more evident in those with private insurance, although the trend did not reach significance.

CONCLUSIONS

Parents of infants with apnoea of prematurity or ALTE are highly compliant with cardiorespiratory monitoring recommendations in the first month of monitor usage. Siblings of SIDS are monitored for fewer hours and are less likely to be monitored on a daily basis.

Effects of perinatal hypoxia on serum unbound free fatty acids and lung inflammatory mediators

Cellular injury during tissue hypoxia is due, in part, to reactive intermediates released by activated leukocytes. We found that the inflammatory mediators tumor necrosis factor (TNF)-alpha, IL-6, and IL-1beta are elevated in situ in lung macrophages on day 14 following exposure of rats to intermittent or chronic hypoxia from birth. Because inflammatory mediators can increase lipolysis in adipocytes, we also measured serum unbound free fatty acids (FFAu)--the biologically active compartment of FFA--in rat pups exposed to intermittent or chronic hypoxia. FFAu values were markedly elevated during the first 2 days of life in all rats, displaying an approximately 3-fold decrease from day 2 to day 3. Exposure to chronic hypoxia significantly increased FFAu levels measured on day 13. Since elevated serum FFAu are known to suppress leukocyte activation, we speculate that increased FFAu levels represent a mechanism for attenuating inflammation and tissue injury following sublethal hypoxia in the perinatal period, either physiologically in the immediate newborn period, or as a late response to ongoing hypoxic insult.

Heart rate and oxygen saturation correlates of infant apnea

OBJECTIVE

To analyze the effects of apnea duration on changes in heart rate and oxygen saturation and to examine the temporal relationships among these variables.

STUDY DESIGN

An event analysis sheet was designed to analyze numerous variables reflecting changes in heart rate and oxygen saturation associated with infant apnea. From July 1, 1991 through June 30, 1992 we identified 32 infants enrolled in The Infant Apnea Program at St. Peter's Medical Center, New Brunswick, NJ who had apnea > or = 15 seconds in duration on consecutive 12-hour multichannel recordings of heart rate, thoracic impedance, nasal thermistry, and oxygen saturation. The apnea epochs of these patients were subdivided into apnea of short (10 to 14 seconds), medium (15 to 19 seconds), and long (> or = 20 seconds) duration, and a total of 236 apnea epochs were analyzed. The significance of differences was assessed by analysis of variance and Newman-Keuls multiple comparisons.

RESULTS

We found that the duration of apnea has significant effects on perturbations in both heart rate and oxygen saturation, however, the degree of oxygen desaturation can not be predicted by the perturbation in heart rate. Analysis of the temporal relationship of apnea, bradycardia, and oxygen desaturation reveals that, although apnea precedes both heart rate and oxygen saturation drops in most infants as the length of apneic interval increases, the interval between apnea onset and associated drops in heart rate and/or oxygen saturation also increases.

CONCLUSION

Oxygen saturation monitoring may provide important physiologic data that can not be assessed by cardiorespiratory monitoring alone.

The apgar score and its components in the preterm infant

OBJECTIVE

The Apgar score is well-characterized in full-term infants but not in premature infants. The objective of this study was to assess the Apgar score in preterm infants with respect to the relationships between the 1- and 5-minute scores, the correlation of the Apgar score with pH and with other variables, and the relationship among the individual Apgar components.

METHODOLOGY

We recorded Apgar scores at 1 and 5 minutes in a population-based cohort of preterm infants (n = 1105) with birth weight <2000 g, from three intensive care nurseries in central New Jersey. Linear correlation analysis was used to examine the relationship between 1- and 5-minute Apgar scores and between the individual components of the Apgar score. Multiple regression analysis was used to explore the relationship between various perinatal characteristics and the Apgar score, and between pH and Apgar score. Stepwise logistic regression analysis was used to assess the determinants of mortality.

RESULTS

The 1-minute Apgar score median (25%, 75%) was 6(4,8) and correlated with the 5-minute score of 8(7,9) at r = .78. Slight but significant differences were seen between male (n = 557) and female (n = 508) infants in the 1-minute (6[4,8] and 7[4,8]) Apgar scores. One- and 5-minute scores of white infants (7[4,8] and 8[7,9]; n = 713) were significantly higher than those of black infants (5[3,7] and 8[6,9]; n = 280). Birth weight and gestational age were both linearly related to both Apgar scores. Low Apgar score (<3 at 1 minute and <6 at 5 minutes) was significantly associated with birth weight, gestational age and mode of delivery. Low arterial blood pH (<7.01) at birth was significantly related to low Apgar score. One hundred fifty-nine infants died; these infants were significantly smaller (983 +/- 382 vs 1462 +/- 369 g), less mature (27 vs 31 weeks), had lower arterial blood pH (7.20 +/- 0.18 vs 7.31 +/- 0.11), had lower 1- (3[2,6] vs 7[4,8]) and 5-minute Apgar scores (6[4,8] vs 8[7,9]), and a greater incidence of low Apgar score (32% vs 6%) than did survivors.

CONCLUSIONS

Among the components of the Apgar score, respiratory effort, muscle tone, and reflex activity correlated well with one another; heart rate correlated less well; and color the least. Our data confirms the limited use of the Apgar score in preterm infants and demonstrates the different responses of the Apgar score's components.